Multi-Inheritance via protocol in OC

There is no concept of multiple inheritance in OC, but we can implement multiple inheritance by protocol

Examples are as follows:

#import <Foundation/Foundation.h>

@protocol ADD <NSObject>

-(int) AddA: (int) a B: (int) b;

@end

#import <Foundation/Foundation.h>

@protocol Sub <NSObject>

-(int) SubA: (int) a B: (int) b;

@end

#import <Foundation/Foundation.h>

@protocol Mul <NSObject>

-(int) Mula: (int) a B: (int) b;

@end

================================================== above is three protocols

Here is a new compute class that inherits from NSObject Calculator

#import <Foundation/Foundation.h>

#import "Add.h"

#import "Sub.h"

#import "Mul.h"

Compliance with multiple protocols

Multiple inheritance similar to C + +

@interface Calculator:nsobject <Add,Sub,Mul>

@end

#import "Calculator.h"

Implementing the methods in the Protocol

@implementation Calculator

-(int) AddA: (int) a B: (int) b {

return a+b;

}

-(int) SubA: (int) a B: (int) b {

return a-B;

}

-(int) Mula: (int) a B: (int) b {

return a*b;

}

@end

==========================================

#import <Foundation/Foundation.h>

#import "Calculator.h"

/*

Now there are multiple classes, one is the Adder class (will be counted addition) the second class is the subtraction Class (subtraction function) The third multiplier class (multiplication)

Implementing a class can be done separately-+

C + + can be implemented with multiple inheritance

But OC does not inherit much but OC can be implemented by protocol.

*/

int main (int argc, const char * argv[]) {

@autoreleasepool {

Calculator *calc = [[Calculator alloc] init];

NSLog (@ "%d", [Calc adda:1 b:1]);//2

NSLog (@ "%d", [Calc suba:1 b:1]);//0

NSLog (@ "%d", [Calc mula:1 b:1]);//1

}

return 0;

}

Multi-Inheritance via protocol in OC